Machine table gage



i 3 sheets sheet 1.

(No Model.) Q 4 O. M. LBTZ. MACHINE TABLE GAGE. 1 No. 336,814. Patented Feb. 23, 1886.

3 Sheets-Sheet 2.

(No Model.)

0. M. L gTiza MACHINE TABLE GAGE.

Patentedfeb. 23, 1886.

fiwaw w l m m i (No Model.) 3 Sheets-Sheet 3 O. M. LETZ.

MACHINE TABLE GAGE.

No. 336,814. Patented Feb. 23, 1886.

MLcJS ed' ,Jnuanr:

UNITED STATES PATENT OFFICE.

CHARLES M. LETZ, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE-HALF TO ALEXANDER ZEESE & (10., OF SAME PLACE.

MACHINE-TABLE GAGE.

SPECIFICATION forming part of Letters Patent No. 336,814, dated February 23, 1886,

Application filed October 14, 1884.

T 0 all whom, it may concern.

Be it known that I, CHARLES M. LETZ, a citizen of the United States of America, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Dovetailing-Mwchines, of which the following is a specification, reference being bad therein to the acconr panying drawings.

My invention relates to an improved dovetailing-machine.

The object it has in view is to obtain asimple and effective machine, by the use of which dovetail grooves and projections may be formed with rapidity and certainty and by the same machine.

To the accomplishment of the above the in vention consists of the novel devices and combination of devices as will be described and claimed.

In the accompanying drawings, Figure l is a top plan View of the machine; Fig. 2, a longitudinal section; Fig. 3, a crosssection, and Figs. 4 and 5 details of parts.

Like letters refer to like parts'in each view.

A represents the bed-plate, and B B the supports, such parts being of any suitable con struction. In the upper face of plate A, and transversely thereof, there is formed a groove, a, in which a guide, 0, is adapted to be moved. This guide consists of a vertical part, b, and a horizontal part, b, the former acting as a guide to determine the position to be occupied by the strip to be operated upon. A vertical pin or screw, 0, is inserted into part b at or about its rear end, said pin being passed up through a slot, (1, formed in a block or frame, D, Fig. 4, and is then secured to a lever, E, which has bearing in block D, as at a.

Block D is provided at its rear end with an extension, f, which is upon a lower plane than the block proper, and is adapted to move in groove a, referred to. Extension f is provided with a slot, g,throngh which a pin, it, is passed, to secure the block D in position on the table, and at the same time allow of the ready adjustment of such block. A small pin, is, may be passed through lever E into an opening, Z,

formed in block D when it is desired to hold Serial No. 145,450. (No model.)

the lever firmly in position, the pin being removed for the adjustment of the parts.

Set-screws m are inserted into slot d of block D, and serve to determine the play of leverE and pin 0, referred to.

Formed with or secured to lever E is an arm, 12, provided with a segmental slot, 0, through which a set-screw, p, is passed, to hold the parts in any given position.

In forming the dovetail groove with this machine, I employ two cutters, the first to cut a straight groove and the second to bevel the edges of the groove thus out. These cutters are situated beneath the bed-plate A with their cutting edges protruding up through suitable openings formed in said bed-plate.

The cutting device used for forming the plain groove consists of a cuttenhead, F, carrying a suitable number of cutters, q, fixed adj nstably and removably therein, as shown in Fig. 2. The cutting-edges of these knives are arranged on the weltknown cross-cut principle to give a clean cut. Gutter-head F is mounted upon a shaft, 1', supported in suitable hangers, s, and carrying a pulley, 25. Belt G is passed around pulley t, and also around a pulley, I-I, keyed to a shaft, K, as shown.

The cutter for forming the bevel consists of a head, L, formed of suitable material, and in shape a truncated cone. Upon two of its upper side edges cutter L is notched, as shown in Fig. 1, this form and construction of the cutter serving to form the bevel to the groove first cut. Cutter L is mounted on a shaft, a, mounted in bearing-boxes v,secured to brackets, as shown in Fig. 3. Power is imparted to this shaft and cutter through the medium of cross-belting M, passing around pulleys N O.

The operation is as follows: The block D is first adjusted upon the table, its position being determined by the thickness of the strip to be operated upon, the parts being arranged to out the groove in the center of the strip, one side edge of which strip will be pressed against the vertical part of guide 0 and be kept in line thereby. The strip is then pushed forward,and as it reaches the firstcutter a straight groove is formed therein, and as it advances the second cutter is met and the bevel formed.

To form the dovetail projection, the pin it is I removed and the guide is moved until it slightly overlaps the cutters, this being allowed by the notch w, and the strip being then fed forward with one side pressing against the guide one side edge is cut away. The guide is moved back until there is sufficient space for the insertion of the strip between the guide and the cutters. As it is then fed forward again it is cut away on the opposite side, and by the two operations the projection is formed. The set-screws referred to serve to limit the movement of the lever and guide,and thereby determine the position of said guide with respect to the cutters, and consequently the depth to which the edges of the strip are out, this being necessary to obtain a projection corresponding in size to any given groove.

\Vhat I claim is- In a dovetailing-machine, the combination,

with the bed-plate A, provided with transverse groove a and with cutters F L, protruding up through openings formed in such bed-plate, of guide 0, consisting of vertical part b and horizontal part b, pin 0, secured to part b, slotted plate D, provided with extension f, moving in groove a and situated on a lower plane than the plate proper, regulatingscrews m,-entering the slot of plate D, lever E, pivoted in plate D and secured to pin a, slotted arm n, secured to the handle end of lever E, and set-screw 1), passed through the slotin such arm, the parts arranged and adapted to operate as and for the purpose set forth.

In testimony whereof I affix my signature inpresence of two witnesses.

CHARLES M. LETZ.

VVituesses:

M. J. OLAGETT, LOUIS NOLTING. 

